Prediction of a Low Success Rate of Astronauts in Space in Performing Endotracheal Intubation

Abstract

We appreciate the letter by Roan and Boyd regarding our article.1Their footnotes are presentations at specialty meetings and no data are available for review; therefore, these footnotes cannot be regarded as legitimately indicating that the Fastrach Laryngeal Mask Airway ™ (LMA ™; LMA North America, Inc., San Diego, CA) has already been used on the space shuttle. We agree that the learning curve should require little experience to master and maintain proficiency. In this letter, we want to explain why we believe that the Combitube® (Tyco Healthcare, Nellcor Mallinckrodt, Pleasanton, CA) is superior to the LMA ™.First, it provides an almost perfect seal against aspiration especially in vomiting and bleeding patients.2–4Second, it allows application of high ventilatory pressures.3Third, the diameter of the Combitube® is very small and therefore allows insertion even in patients with a small interincisor distance and/or trismus. Fourth, training time is short.5Fifth, studies with the Combitube® show that skills are not only easily acquired but also easily maintained even in small emergency medical systems when the device is used only once in a period of 18 months.2–4Sixth, all studies directly comparing the LMA ™ and the Combitube® are in favor of the Combitube®: Emergency medical technicians rate the Combitube® best with regard to overall performance and adequacy of airway patency and ventilation; success rates of insertion and ventilation are highest with the Combitube®.3Seventh, significantly more emergency care physicians prefer the Combitube® as a nonsurgical alternative for coniotomy as compared with the LMA ™.5Physicians rate the Combitube® best with regard to effectiveness and easiness to learn.5Eighth, the Combitube® has proven to be a salvage airway when conventional rapid sequence tracheal intubation fails with no reported complications.6Ninth, the Combitube® is used as a salvage airway by anesthesiologists when tracheal intubation or LMA ™ fail in out-of-operating-room resuscitation.7We strongly emphasize training of whatever device is being used. Although the LMA ™ provides a fascinating outstanding concept for in-hospital routine use, the obstacles of inadequate prevention of aspiration and inability to apply high ventilatory pressures limit its value in emergencies.*Medical University, Vienna, Austria. michael.frass@meduniwien.ac.at